Folding fire escape ladder

ABSTRACT

A folding fire escape ladder has an L-shaped first upright adapted to be secured vertically to the side of a building and has an L-shaped second upright parallel to but reversely positioned with respect to the first upright. A plurality of rungs are connected to both uprights, each rung having parallel end portions and an offset intermediate portion, the rungs being pivotally connected at the end portions to the uprights by shoulder rivets having enlarged, flanged heads. Other shoulder rivets extend from the uprights and are positioned to engage the margins of the rung to serve as stops, the other rivets also having enlarged flanged heads adapted to engage one side of the rung as positioners. A latching lever adapted to engage the first upright is releasably held against a fulcrum on the second upright by a spring, there being an actuating cable attached to the lever and to the second upright.

United States Patent I [72] Inventor Cheyenne A. Reinhard 594 BeatriceSt., San Leandroc, Calif. 94579 [2]] Appl. No. 861,684 [22] Filed Sept.29, 1969 [45] Patented Apr. 20, 1971 [54] FOLDING FIRE ESCAPE LADDER 3Claims, 3 Drawing Figs.

[52] U.S.Cl 182/160, 182/96 [51] Int.Cl. E06c U383 [50] Field of Search182/159, 160, 96, 95

[56] References Cited UNITED STATES PATENTS 250,901 12/1881 Dunn 182/96314,899 3/1885 Wilson 182/96 350,047 9/1886 Dunn 182/96 1,026,097 5/1912Lewis 3,414,081 12/1968 Wedvik....

Primary ExaminerReinaldo P. Machado Att0rneyLothrop and West ABSTRACT: Afolding fire escape ladder has an L-shaped first upright adapted to besecured vertically to the side of a building and has an L-shaped secondupright parallel to but reversely positioned with respect to the firstupright. A plurality of rungs are connected to both uprights, each runghaving parallel end portions and an offset intermediate portion, therungs being pivotally connected at the end portions to the uprights byshoulder rivets having enlarged, flanged heads. Other shoulder rivetsextend from the uprights and are positioned to engage the margins of therung to serve as stops, the other rivets also having enlarged flangedheads adapted to engage one side of the rung as positioners. A latchinglever adapted to engage the first upright is releasably held against afulcrum on the second upright by a spring, there being an actuatingcable attached to the lever and to the second upright.

IFOLlDlNG FIRE ESCAPE LADDER The invention relates to means which can bepermanently installed on the side of a building, such as an officebuilding or a dwelling or the like, and which normally is unobtrusiveand out of the way. The device is located, however, so that in theeventof an emergency, such as a fire, a user can quite readily and easilyactivate the ladder so that it becomes immediately available for descentor ascent by persons, even persons of considerable weight orsimultaneously by a large number of persons.

It is an object of the invention to provide a folding fire escape ladderthat normally will be quite unobtrusive and unobjectionable as toappearance when installed on the side of a building near emergencyexits, such as doors, balconies, windows and the like.

Another object of the invention is to providea folding fire escapeladder that can unfailingly and always, even after long periods ofdisuse, be erected quickly into its condition for easy use.

Another object of the invention is to provide a latching mechanism whichwill under any circumstances release in an emergency.

A further object of the invention is to provide securing devices andstops to make sure that the ladder, when unfolded or extended, issufiiciently firm and rigid in its extended position to support theweight of a large number of persons.

A further object of the invention is to provide a folding fire escapeladder that when extended is sufiiciently stiff and firm in alldirections to afford a reassuring and adequate support for persons usingit in an emergency.

A still further object of the invention is to provide a folding fireescape ladder that remains workable despite its exposure to the elementsduring a protracted period of time.

Other objects together with the foregoing are attained in the embodimentof the device described in the accompanying description and illustratedin the accompanying drawing, in which:

FlG. l is a front elevational view of a folding fire escape laddererected against the side of a building and shown in broken lines in itsopen position and shown in full lines in its folded position;

- H6. 2 is an enlarged view like FIG. 1, but showing related portions ofthe structure of FIG. l in an extended or unfolded position; and

FIG. 3 is a cross section, the plane of which is indicated by the line3-3 of FllG. 2.

While the folding fire escape ladder pursuant to the invention can beincorporated in a large number of different ways, depending particularlyupon the environment or use to which it is especially to be put, it hasin practice successfully been embodied as illustrated herein. in thisinstallation the device is utilized on the side of a building 6 which ispresumed to have various egress openings adjacent to the location of theladder, some of them being nearer thev bottom of the ladder and othersbeing nearer the top thereof.

The ladder includes an L-shaped first upright 7', This is convenientlyan angle member, preferably fabricated of relatively stiff, aluminumalloy which will hold itsshape well under load and which includes oneleg 3 and an adjacent leg 9 at right angles to the first leg.Preferably, the leg 9 is disposed parallel to and adjacent the sidewallof the building 6 and isfastened thereto by means of several spacedbrackets 11. These are not only held to the building by'suitablefastenings l2, such as lag bolts or the like, but are also secured tothe first upright 7 by fastenings, such as nuts and bolts 13. Thedisposition of the first upright is with the flange or leg 8 extendingout from and disposed at right angles to the side plane of the building6.

Pursuant to the invention there is. also provided a second uprightmember 16, likewise of generally angular formation the same as orcomplementary to the formation of the member 7. That is to say, thesecond upright has a flange 17' arranged substantially parallel to theflange or leg 9 and hasa flange 18 at aright angles to the flange l7 anddisposed substantially parallel to the flange or leg 3. The uprights areso disposed with respect to each other that when they are close togetherthey define a generally boxlike configuration to serve as a partialhousing.

To maintain the uprights in their various desired positions, 1 provide aplurality of rungs 21 as connectors. Each rung is like the others sothat a description of one applies also to the others. A rung 21, forexample, is a strap of similar metal generally flat at its opposite ends22 and 23. The planar ends are disposed parallel to each other. Theintermediate portion 24 of each rung has an angular offset so that oneend 22 can die close to the flange 8 whereas the other end 23 can lieclose to the flange R8. The rung 21 if desired can have portionssomewhat rounded or shaped (not shown) for convenient grasping and thelike.

Each of the rungs 21 at the end 22 is pivotally connected to the firstupright 7 by means of a shoulder rivet 26. This rivet (HO. 3) has anarrow anchor portion 27 and an adjacent enlarged portion 28 affordingan intermediate shoulder designed to butt against the inner face of theflange 3. The flange is first perforated, a rivet is forced in until theshoulder abuts, and then the rivet is deformed as at 29 so that is isfirmly held in position. The rung end 22 is accordingly pierced toprovide ajoumal slightly larger than the portion 28 so that the rung ispivotally mounted free rotation. The fit is relatively loose on thejournal so that even surfaces deteriorated after long exposure willstill rotate. in order to hold the rung in position against lateraldislodgement despite a loose journal the rivet has an end flange 31designed to overlap and to lie closely adjacent the side of the rung 21.In a similar fashion the flange 18 is similarly pierced and carries ashoulder rivet 32 of a similar configuration having an enlarged flange33 lying against the side of the rung 21 to hold it against axialdislodgement at that end.

To make certain that the rung lies in appropriate, horizontal positionwhen the ladder is unfolded l provide on the flange 3, for each of therungs, another shoulder rivet 34 disposed so that its intermediateportion 36 lies tangent to the lower edge of the rung 21 when the rungis extended horizontally and so that the enlarged flange 37 on the stoprivet lies against the face of the rung. ln-this way the end 22 of therung cannot be dislodged laterally or transversely and is well supportedfrom below. ln addition, I provide a similar stop rivet 33 on the flange18 disposed so that its intermediate portion 39 is abutted by the topedge of the end 23 of the rung 21 when the rung is in horizontalposition, In this case the enlarged flange 41 of the second stop rivetlies against the opposite side of the rung from the flange 37 andprevents any lateral shaking or displacementof the rung or of the secondupright 16 despite loose pivots.

Great careis taken to position the pivot rivets 26 and 32 far from theirassociated stop rivets 34 and 38 for substantial leverage while keepingthe stop rivet flanges 37 and 41 substantially tangent to the uprightedges so as to permit compact folding of the uprights. The stop rivetsare also carefully placed so as to have all of the stop shoulder rivetsengage their respective rungs substantially simultaneously.

Partly for that reason, the ability of the structure to remain stiff andunshakingwhen extending and to bear loads is more than adequate. Theladder, when extended, can bear the weight of anumber of people at once.Even if a person puts his weight on the ladder before it is completelyextended, nevertheless the ladder will open and assume its stop positionwithout shock or failure.

ln use the ladder'is normally in folded condition. For that reasonthereis provided a catch mechanism generally designated 13. This catchis mounted on a fulcrum 44 provided by a restricted notch as cut in theflange 17 A bowed portion 47 of the lever 48 bears against the fulcrum.A hook 49 on the end'of the lever in one position lies behind the flange9. A spring 51 extends from an anchor 52 of the lever to an anchor 53 onthe flange l7 and also holds the lever onits fulcrum seat. An actuatingcable 54 extends from one end'of the lever 48 to an anchor 56 on theflange 17 preferably a number of feet above the ground so that it isregularly accessible to adults but is not so accessible to children.

Even though the hook may be engaged for a long time, say a number ofyears, without any operation, then when an emergency exists and thecable 54 is pulled, the hook 49 is readily disengaged. if there shouldbe a mischance and the hook itself does not immediately release, aperson can readily dislodge the entire lever 48 from its fulcrum seatagainst the retention of the spring and can in that fashion disengagethe holding device. When released, the outboard upright member 16 willswing away by gravity from its boxlike configuration with the member 7and will descend until all of the rungs are horizontal and rest againsttheir various stop rivets in what amount to grooves between the flangesof the uprights and the enlarged flanges of the rivets. The entirestructure when extended is extremely rigid and stiff and can readilywithstand the descent of persons. The ladder is restored to its originalcondition simply by forcing the outer member back into its positionagainst the inner member and with the hook again engaged.

lclaim:

l. A folding fire escape ladder comprising a first upright L- shaped intransverse cross section, means for securing said first upright to asupport such as a building wall, a second upright L-shaped in transversecross section arranged parallel to and facing opposite to said firstupright, a plurality of cross rungs of flat material, a first shoulderrivet having its shoulder abutting said first upright and pivotallyconnecting one end of one of said rungs to said first upright, a secondshoulder rivet having its shoulder abutting said first upright andmounted in said first upright in position to abut a lower surface onsaid one rung when said one rung is in a horizontal position, anenlarged flange head on said second shoulder rivet adapted to engage theside of said one rung opposite said first upright when said one rung isin a horizontal position, a third shoulder rivet having its shoulderabutting said second upright and pivotally connecting the other end ofsaid one rung to said second upright, a fourth shoulder rivet having itsshoulder abutting said second upright and mounted in said second uprightin position to abut an upper surface on said one rung when said one rungis in said horizontal position, an enlarged flange head on said fourthshoulder rivet adapted to engage the other side of said one rungopposite said second upright when said one rung is in a horizontalposition, and said one rung having substantially planar ends withparallel edges each adapted to engage a respective one of said secondand fourth shoulder rivets between said uprights and said flange headsand having an intermediate portion angled to dispose said uprights in abox relationship when said uprights are close together.

2. A folding fire escape ladder as in claim 1 in which said first andthird shoulder rivets also have enlarged flange heads, each of saidflange heads being positioned and adapted to overlie and substantiallyengage a different one of the opposite sides of said one rung.

3. A folding fire escape ladder as in claim 1 including a hook leverhaving an open bowed portion intermediate its ends, means on said secondupright for providing a fulcrum adapted to lie in said bowed portion ofsaid hook lever, a spring engaging said hook lever and said secondupright for releasably urging said bowed portion of said hook leveragainst said fulcrum, a hook on one end of said hook lever adapted toengage one end of said first upright, and a cable engaging the other endof said hook lever for pulling said hook lever to tension said springand for pulling said bowed portion of said hook lever bodily from saidfulcrum.

1. A folding fire escape ladder comprising a first upright Lshaped intransverse cross section, means for securing said first upright to asupport such as a building wall, a second upright Lshaped in transversecross section arranged parallel to and facing opposite to said firstupright, a plurality of cross rungs of flat material, a first shoulderrivet having its shoulder abutting said first upright and pivotallyconnecting one end of one of said rungs to said first upright, a secondshoulder rivet having its shoulder abutting said first upright andmounted in said first upright in position to abut a lower surface onsaid one rung when said one rung is in a horizontal position, anenlarged flange head on said second shoulder rivet adapted to engage theside of said one rung opposite said first upright when said one rung isin a horizontal position, a third shoulder rivet having its shoulderabutting said second upright and pivotally connecting the other end ofsaid one rung to said second upright, a fourth shoulder rivEt having itsshoulder abutting said second upright and mounted in said second uprightin position to abut an upper surface on said one rung when said one rungis in said horizontal position, an enlarged flange head on said fourthshoulder rivet adapted to engage the other side of said one rungopposite said second upright when said one rung is in a horizontalposition, and said one rung having substantially planar ends withparallel edges each adapted to engage a respective one of said secondand fourth shoulder rivets between said uprights and said flange headsand having an intermediate portion angled to dispose said uprights in abox relationship when said uprights are close together.
 2. A foldingfire escape ladder as in claim 1 in which said first and third shoulderrivets also have enlarged flange heads, each of said flange heads beingpositioned and adapted to overlie and substantially engage a differentone of the opposite sides of said one rung.
 3. A folding fire escapeladder as in claim 1 including a hook lever having an open bowed portionintermediate its ends, means on said second upright for providing afulcrum adapted to lie in said bowed portion of said hook lever, aspring engaging said hook lever and said second upright for releasablyurging said bowed portion of said hook lever against said fulcrum, ahook on one end of said hook lever adapted to engage one end of saidfirst upright, and a cable engaging the other end of said hook lever forpulling said hook lever to tension said spring and for pulling saidbowed portion of said hook lever bodily from said fulcrum.